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Cod hatcheries rely greatly on wild-caught broodstock as egg quality from farm-reared broodstock tends to be poor. Broodstock diet and levels of essential fatty acids have been linked to fecundity and egg quality in cod. Arachidonic acid (ARA) and astaxanthin (Ax) are important nutrients linked to fish egg quality and differences in levels have ben found between eggs from wild and farmed cod. The aim of this thesis was to investigate the impact of dietary supplementation with ARA and Ax on fecundity and egg quality in cod. The first experiment investigated the effect of feeding a diet supplemented with ARA, for 1, 2 or 3 months prior to peak spawning. Results showed that supplementation increased ARA in eggs and that Groups fed the supplement had improved fecundity and egg quality (though with no correlation between the duration of supplementation and number/quality of eggs). The second experiment investigated the effect of supplementation of Ax in broodstock diets on egg quality in farmed cod and showed that Ax was taken up into eggs and that fish fed supplemented diet had improved fecundity and egg quality. The third experiment compared the effect of diet supplementation with ARA and Ax on egg quality in wild and farmed cod and showed that despite the dietary supplementation, wild origin fish performed better on a number of egg quality and fecundity indices. However, it was not possible to take the greater ages and spawning experience of the wild broodstock into account, which may have influenced the results. The fourth experiment measured lipid and fatty acid profiles of eggs from two UK cod hatcheries. Variation was found between farms and across seasons. Results showed that supplementation of cod broodstock diet with ARA and Ax had a positive impact on egg quality and fecundity, although effects were not consistent across all egg quality parameters.

This study investigated whether lutein and DHA enriched egg consumption can improve electrophysiological retina function for the prevention of age-related macular degeneration in Caucasian older adults. Thirty (male: n=11, female: n=19) healthy Caucasian older adults (64.0 ± 3.4 years) consumed two lutein and DHA enriched eggs (0.87 mg lutein/day, 220 mg DHA/day) daily for six weeks. Retina function, plasma and red blood cell (RBC) DHA, plasma lutein, lipid profiles, and lipoprotein subfractions were assessed at day 0 and 6 wks. The maximum amplitude of scotopic a-wave and photopic b-wave significantly increased along with plasma DHA concentrations No significant alterations in plasma Chol, HDL-Chol, LDL-Chol, triacylglycerides, plasma lutein and RBC DHA were present. A significant increase in large HDL particles and a decrease in intermediate sized HDL particles occurred. This study suggests that consuming two lutein and DHA enriched eggs daily may improve electrophysiological retina function without adversely altering plasma lipids in Caucasian older adults. / May 2017

This study focuses on the analysis and assessment of competitiveness within the Uruguayan broiler industry. Porter's (1990) 'national diamond' was selected as the appropriate framework for analysis and was applied to the six major Uruguayan broiler firms. This research reveals that the unique characteristics of the Uruguayan broiler industry are successfully accommodated within the selected framework to explain the success of the broiler industry against other meat substitutes. Therefore, this study has confirmed Porter's (1990) diamond system as an adequate conceptualization of success in the Uruguayan broiler industry. These results are consistent with those found in the existing literature, lending support to the view that Porter's (1990) model seems to be applicable to developing countries such as Uruguay. However, some modifications of the model are required to fully explain the progress of this industry. This research project presents an adaptation of Porter's (1990) 'diamond' to the singularities of the firms investigated in this study. This study opted for an industry-level case study research strategy that is operationalized through in-depth personal interviews with owner directors and managers in six of the seven possible organizations within Uruguay. This is augmented by further data collection (additional interviews) through sources in government and market relevant bodies in order to generate information on the national context. The selected research method showed its utility for the investigation of weaknesses and strengths within the Uruguayan broiler industry. These findings were used to accomplish the second objective of this research which was to elaborate policy recommendations out of the primary and secondary collected data that would help Uruguayan broiler firms to compete with international broiler firms in a regional economic block (MERCOSUR) without barriers.

Doctor of Philosophy / Department of Agricultural Economics / Hikaru Hanawa Peterson / Consumers’ food demand has been found to be affected not only by prices and income, but also by their increasing concern about factors like health benefits, animal welfare, and environmental impacts. Thus, many food producers have differentiated and advertised their products using relevant attributes. The increasing demand and supply of differentiated food products have raised questions regarding consumer preferences and producer strategies. This dissertation consists of three essays and empirically examines the egg market to shed light on related issues. The first question that this study aims to answer is whether consumers are willing to pay a premium for livestock and dairy products associated with improved animal welfare. Consumers’ attitude towards such products not only affect manufacturers’ production decisions, but also influence policy makers and current legislations. Using a national online survey with choice experiments, the first essay found that consumers in the study sample valued eggs produced under animal-friendly environment, suggesting incentives for producers to adopt animal welfare friendly practices. In an actual shopping trip, consumers usually need to choose from products with multiple attributes and labels. Studying how consumers with heterogeneous preferences process these information simultaneously and make decisions is important for producers to target interested consumer segments and implement more effective labeling strategies. In the second essay, a different national online survey was administered. The analysis using a latent class model categorized the sample respondents into four classes, and their preferences toward attributes and various label combinations differed across classes. Scanner data, which record actually purchased choices, are an important source of information to study consumer preferences. Diverging from the traditional demand approaches that are limited in studying differentiated product markets using scanner data, this study used a random coefficient logit model to overcome potential limitations and examine the demand relationship as well as price competition in the differentiated egg market. The third essay found that conventional and private labeled eggs yielded higher margins due to less elastic demand and cautioned producers of specialty eggs, which are usually sold at high prices despite their much more elastic demand.

Master of Science / Food Science / Fadi Aramouni / Due to an increase in awareness of celiac disease, the gluten-free market continues to expand. However, gluten-free breads are still characterized by a poor structure and overall mediocre quality. This research was aimed at determining the impact of egg addition as well as an antistaling agent (DATEM) on the quality of a batter-based gluten-free sorghum bread. Gluten-free bread loaves containing 20, 25, or 30% eggs (as is) on a flour basis were evaluated against a control (no egg). The impact of the antistaling agent, DATEM at 0.5% was also studied for each of these formulations. Quality factors evaluated included water activity, color, specific volume, and cell size. Texture profile analysis was performed to evaluate staling rate based on changes in crumb hardness values and a trained panel evaluated staling attributes by descriptive analysis. Finally, a consumer acceptance test on sorghum bread with and without eggs was also conducted. Results showed that sorghum breads with eggs had higher specific volumes than control (increase from 0.06 cm[superscript]3/g to 0.11 cm[superscript]3/g), while DATEM had a negative effect on the volume of gluten-free bread (decrease of 0.73 cm[superscript]3/g). Eggs also improved cell structure and produced significantly darker crust (p<0.05). Additionally, the addition of eggs reduced bread hardness (from 54 g force to 142 g force on fresh bread) and slowed the rate of staling over the 12 day storage period studied. Descriptive analysis results confirmed the findings of the texture analysis, showing control bread significantly harder (p<0.05) than egg-containing bread at days 0 and 4. The consumer test indicated a significant preference (p<0.05) for sorghum bread with eggs over the control. The overall acceptability score for this bread was above 6 on a 1 to 9 hedonic scale. The score was closer to 7 when the bread was rated by consumers with celiac disease. This research proved that the addition of eggs to a gluten-free sorghum bread formulation resulted in delayed staling and better overall quality and acceptability of the product.

Call number: LD2668 .T4 1957 T58 / Master of Science

Typescript (photocopy). / Digitized by Kansas Correctional Industries / Department: Animal Sciences and Industry.

Foram utilizadas 750 poedeiras comerciais de linhagens brancas com 23 semanas ao início do período experimental, distribuídas num delineamento em blocos completos aleatorizados sendo estes caracterizados pela oncatenação das linhagens com coluna de gaiolas; os tratamentos foram cinco densidades ou taxas de lotação na gaiola (321,43; 375; 450; 562,50 e 750 cm2/ave) com seis repetições, totalizando 150 parcelas experimentais. As dietas experimentais foram à base de milho e farelo de soja, formuladas para suprir as exigências nutricionais das linhagens em todas as fases. O desempenho produtivo e econômico foram avaliados através do peso dos ovos (g), percentagem de postura (%), massa de ovos (g/ave/dia), consumo de ração (g/ave/dia), conversão alimentar por dúzia (kg/dz) e por quilo de ovo (kg/kg). A qualidade de ovos foi avaliada através da gravidade específica (GE), unidades Haugh (UH), percentagens de gema, albúmen e casca, espessura da casca (EC), resistência à quebra (RQ), coloração da gema e índice gema (IG). O bem-estar das aves foi avaliado através de indicadores clínicos, imunológicos e fisiológicos. Para efeito da avaliação dos resultados, foram estabelecidos seis blocos com repetições internas. Os dados foram analisados com auxílio do SAS, sob modelo misto, considerando os efeitos da densidade, período e a interação entre estes, como fixos, além dos efeitos aleatórios de bloco e resíduo. Por se tratar de medidas repetidas longitudinalmente, buscou-se a melhor estrutura de covariância para cada variável. Quando adequado foi aplicado o teste de tukey-kramer para a comparação de médias (p&lt;0,05). O menor consumo de ração, CA/dz de ovos e melhor desempenho econômico, foram obtidos pela densidade 321,4 cm2/ave. Altas densidades de alojamento não influenciaram a qualidade interna de ovos, a % casca e RQ, mas essas variáveis tiveram efeitos dos períodos, com os melhores valores nos primeiros períodos. Altas densidades tiveram efeitos negativos sobre a GE e EC, principalmente no pico de postura das aves. Os ovos avaliados encontravam-se dentro dos valores desejados, mesmo nas maiores densidades, podendo ser classificados como de excelente qualidade. A densidade de alojamento não interferiru (p&gt;0,05) na avaliação clínica das aves, mas o maior espaço proporcionado nas gaiolas do sistema covencional conferiu menor freqüência de lesões nas aves, indicando promoção e melhora ao seu bem-estar geral. Dados de freqüência cardíaca e temperatura da cloaca estavam dentro dos padrões de normalidade para a espécie. Não foram observadas diferenças (p&gt;0,05) das densidades na resposta imunológica das aves, com os títulos dos anticorpos vacinais contra as doenças de Gumboro e Newcastle acima dos níveis do ponto de corte (cutoff). Os tratamentos não modificaram o perfil sanguíneo das aves e não foi possível caracterizar um padrão de corticosterona no plasma e de excreção de metabólitos fecais de glicocorticoides. A técnica de enzimoimunoensaio, empregada utilizando anticorpo primário contra corticosterona e anticorpo secundário anticoelho de cabra, foi capaz de detectar as variações nas concentrações de corticosterona nesses tecidos, contudo, o entendimento do significado desses achados ainda necessita de novas investigações. / 750 commercial laying hens of white strains aged 23 weeks at the beginning of the experimental period were used, distributed in a randomized complete block design, these being characterized by the concatenation of the strains with column of cages; the treatments were five densities or stocking rates in the cage (321,43, 375, 450, 562.50 and 750 cm2/bird) with six replications, amounting to 150 experimental plots. The experimental diets were on the basis of corn and soybean meal, formulated to meet the nutritional requirements of the strains in all the phases. Both the productive and economic performances were evaluated through the weight of the eggs (g), percentage of laying (%), egg mass (g/bird/day), feed intake (g/bird/day), feed conversion per dozen (kg/dozen) and per kg of egg (kg/kg). Egg quality was determined through specific gravity (SG), Haugh units (HU), percentages of yolk, albumen and shell, shell thickness (ST), resistance to breaking (BR), yolk coloration and yolk index (YI). The welfare of the birds was evaluated through clinical, immunological and physiological indicators. For the purpose of evaluation of the results, six blocks with internal replications were established. The data were analyzed with the aid of SAS, under a mixed model, considering the effects of density, period and the interaction between them, as fixed, in addition to the random effects of block and residue. For se tratar de measures longitudinally repeated, the best covariance structure for each variable was sought. When appropriate, the Tukey-Kramer test was used for comparison of means (p&lt;0.05). The lowest feed intake, FI/dozen of eggs and best economic performance, were obtained at the density of 321.4 cm2/bird. High housing densities did not influence the internal quality of the eggs, % shell and BR, but these variables had effects from the periods, with the best values in the early periods. High densities had negative effects on SG and ST, mainly at the laying peak of the birds. The eggs checked lie within the desired values, even at the highest densities and can be classified as of excellent quality. The housing density did not interfere (p&gt;0.05) in the clinical evaluation of the birds, but the greater space provided in the cages of the conventional system conferred a lower frequency of lesions in the birds, indicating promotion and improvement to their general welfare. Data of heart rate and cloacal temperature were within the normal limits for the species. No differences (p&gt;0.05) of the densities in the immune response of the birds, with the titers of the vaccine antibodies against Gumboro and Newcastle diseases above the cutoff levels were found. The treatments did not modify the blood profile of the birds and it was not possible to characterize a standard of plasma corticosterone and excretion of fecal metabolites of glucocorticoids, but the enzyme immunoassay technique, using primary antibody against corticosterone and secondary goat anti-rabbit antibody, was capable of detecting variations in the corticosterone concentrations in these tissues, however, the understanding of the meaning of these findings still requires further investigation.

Orientador: Edney Pereira Silva / Coorientador: Nilva Kazue Sakomura / Banca: Sandra Regina Freitas Pinheiro / Banca: Márcia Helena Machado da Rocha Fernandes / Resumo: Compreender o metabolismo energético das aves e como a energia é utilizada para mantença, ganho de peso e produção de ovos, permite a elaboração e avaliação de modelos que estimam a exigência nutricional considerando as diferenças de peso corporal (P), ganho de peso (GP) e massa de ovo (MO) na avicultura industrial. Objetivou-se com esta pesquisa analisar os coeficientes que representam a partição da energia ingerida por codornas japonesas na fase de produção de ovos, a partir de um estudo dose-resposta. Foram utilizadas 70 codornas japonesas da linhagem VICAMI®, com 24 semanas de idade, durante 8 semanas, alojadas em galpão convencional. Duas dietas foram formuladas, uma com alto (3.600 kcal/kg) e a outra com baixo (2.100 kcal/kg) teor de energia. Para modificar a energia retida pelas aves, foi empregada a técnica da diluição, obtendo os níveis crescente de energia metabolizável da dieta. Foram utilizados sete tratamentos distribuídos inteiramente ao acaso, com dez repetições e uma codorna por unidade experimental. Os tratamentos foram 2.118; 2.381; 2.557; 2.776; 2.908; 3.171 e 3.435 kcal/kg, com base na composição analisada das dietas determinadas em ensaio de metabolismo. As variáveis analisadas foram ingestão de energia metabolizável (IEM), produção de calor (PC) e energia retida (ER) expressas em kcal/kg0,67. A energia metabolizável para mantença (EMm) foi obtida a partir da relação entre ER e IEM, considerando a condição ER = 0. A exigência metabolizável para ganho de p... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: To understand the energy metabolism of birds and how energy is used for maintenance, weight gain and egg production, allow the elaboration and evaluation of models that estimate the nutritional requirement considering the differences of body weight (BW), body weight gain (BWG) and egg mass (EO) in industrial poultry. The objective of this research was to analyze the coefficients that represent the partition of the energy ingested by Japanese quails in the egg production phase, from a doseresponse study. In a conventional shed it was housed 70 Japanese quails of VICAMI® line, at 24 weeks old, during 8 weeks. Based on the dilution technique it was formulated two energy levels diets, one with high (3,600 kcal/kg) and other with low (2,100 kcal/kg). Seven treatments were randomly distributed, with ten replicates and one quail per experimental unit. Treatments were levels of metabolizable energy in the diet being: 2,118; 2,381; 2,557; 2,776; 2,908; 3,171 and 3,435 kcal/kg. The variables analyzed were metabolizable energy intake (MEI), heat production (HP) and retained energy (RE) expressed in kcal/kg0.67. The metabolizable energy for maintenance (MEm) was obtained from the relation between RE and MEI, solving the equation RE = 0. The metabolizable requirement for weight gain (MEg) was estimated by the relation between use efficiency of energy (k) and net energy for gain (NEg). The metabolizable energy requirement for egg mass (MEe) was obtained by the relation between energy retained in the egg, divided by the energy utilization efficiency for egg mass (ke). The estimated values for MEm, MEg, MEe were 155.60 kcal/kg BW0.67, 5.89 kcal/g and 2.74 kcal/g; respectively. The models that predict MEI based on the parameters that represent the energy requirement ... (Complete abstract click electronic access below) / Mestre